Research

Duration of resuscitation efforts and survival after in-hospital cardiac arrest

Comments on the duration of CPR following the publication of 'Duration of resuscitation efforts and survival after in-hospital cardiac arrest: an observational study' Goldberger ZD et al. Lancet.

In a study published online in the Lancet on 5th September 2012, Goldberger et al. used the American Heart Association’s Get with the Guidelines-Resuscitation (GWTG-R) registry to evaluate a potential association between duration of CPR and survival after in-hospital cardiac arrest. Some of the key results from this study include:

The authors analysed data from 64,339 patients with cardiac arrests at 435 hospitals in the United States during 2000 to 2008.

They have shown an association between duration of resuscitation attempt in non-survivors (as an indicator of the overall tendency to attempt resuscitation for longer) and the rate of survival to hospital discharge.

Hospitals were classified into quartiles based on their median duration of resuscitation among non-survivors: 16, 19, 22, and 25 minutes respectively. Patients at hospitals with the longest resuscitation attempts in non-survivors had a 12% higher likelihood of achieving return of spontaneous circulation (ROSC) and survival to discharge compared with patients at hospitals with the shortest resuscitation attempts in non-survivors.

Overall, the median resuscitation duration was 17 minutes; ROSC was achieved in 48.5%, and 15.4% survived to hospital discharge.

Of those achieving ROSC, it was achieved in 45% by 10 minutes and in 87.6% by 30 minutes.

Of those surviving to hospital discharge, 730 (8.4%) did not achieve ROSC until after 30 minutes of CPR.

The proportion of patients with a good neurological outcome (82%) was the same across all median resuscitation duration quartiles.

Comment

There are inevitably limitations to a study that relies on a retrospective analysis of a database, even if this is very large. The association between median duration of resuscitation attempts in non-survivors and outcome in all patients may result from some unmeasured confounders: duration of a resuscitation attempt may be linked with the delivery of higher-quality CPR and better teamwork; hospitals with higher median duration of resuscitation attempts may tend to provide a more comprehensive package of post cardiac arrest care; and infrequent implementation of do-not-attempt CPR (DNACPR) decisions might lead to shorter median resuscitation durations because the resuscitation team might tend to stop earlier in cases that are clearly futile.

A randomized study is not ethically possible but we hope that further observational data from other national audits such as the UK National Cardiac Arrest Audit (NCAA) will help to help confirm or refute these findings.

Current Resuscitation Council (UK) Guidelines (and international guidelines) do not include specific recommendations on the duration of in-hospital cardiopulmonary resuscitation. This latest research implies that in some cases attempting resuscitation for longer may result in more survivors. It reassures us that prolonged resuscitation attempts do not result in a substantial increase in survivors with severe neurological injury.

Recommendations

The evidence remains insufficient to recommend a minimum duration for an in-hospital resuscitation attempt; instead, the duration should be determined on a case-by-case basis and take into account other known determinants of survival.

Prolonged CPR can result in high-quality survival – if the patient has a potentially reversible cause for cardiac arrest it may be worth continuing CPR for longer.

To improve outcomes and decrease variability, all hospitals should audit their cardiac arrests (ideally submitting these data to NCAA) and benchmark outcomes as part of a quality improvement programme.